We look at the division of 508891 by 3 
We want to figure out the number of times 508891 can be divided by 3.

Step 1:
3 can be fit into 5 1 times, resulting in a remainder of 2.
Use 1 as the next digit of our solution. 
Result so far: 1.0
If we take 3 away from 5, we end up with 2.
Bring next digit (0) of the dividend behind the 2 and repeat the process: 20 / 3

On to step 2:
The number 3 fits into 20 6 times, leaving a remainder of 2.
The number 6 becomes the next digit in our result. 
Result so far: 16.0
Subtract 18 from 20 to get 2.
Fetch the next digit (8) from the dividend, attach it to 2 and continue: 28 / 3

Going ahead to step 3:
3 goes into 28 9 times with a remainder of 1.
Put 9 as the next digit of the answer. 
Result so far: 169.0
Subtracting 27 from 28 leaves us with 1.
Grab the next digit (8) from the dividend, add it to 1, then carry on: 18 / 3

Advancing to step 4:
18 divided by 3 is 6 with a remainder of 0.
Use 6 as the next digit of our solution. 
Result so far: 1696.0
Subtract 18 from 18 to get 0.
Take the next digit (9) from the dividend and append it to 0, then repeat: 9 / 3

On to step 5:
If we divide 9 by 3, we get 3 and a remainder of 0.
The number 3 becomes the next digit in our result. 
Result so far: 16963.0
If we subtract 9 from 9, we get 0.
Append the next digit (1) from the dividend to 0 and continue with: 1 / 3

Step 6:
The number 3 fits into 1 0 times, leaving a remainder of 1.
Write down 0 as next digit of the result. 
Result so far: 169630.0
The remainder is 1 after subtracting 0 from 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

On to step 7:
When dividing 10 by 3, we get 3 with a remainder of 1.
Write down 3 as next digit of the result. 
Result so far: 169630.3
Subtract 9 from 10 to get 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

On to step 8:
10 divided by 3 is 3 with a remainder of 1.
The number 3 becomes the next digit in our result. 
Result so far: 169630.33
Subtracting 9 from 10 leaves us with 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

The final result is 169630.33 with a remainder of 0.001.